Doppler Effect is the change in frequency of light, radio or sound waves when source and receiver are in relative motion.
A form of ultrasound that reflects motions such as fetal heartbeats-in the form of audio signal.
The relationship of the apparent frequency of waves, as of sound, light, and radio waves, to the relative motion of the source of the waves and the observer, the frequency increasing as the two approach each other and decreasing as they move apart.
change in apparent frequency of a wave due to motion of source or receiver.
Austrian physicist famous for his discovery of the Doppler effect (1803-1853)
a device that uses high frequency sound waves to assess blood movement
a machine that can hear the baby's heart beat at a very early fetal age by magnifying the baby's heart beat
A form of ultrasound that reflects motion- such as the fetal heartbeat- in the form of audio signals.
A form of ultrasound. Doppler effect creates an image by bouncing sound waves off an object. It is used to assess the characteristics of blood flow.
a small machine that generates and audible signal by ultrasound, characterizing blood flow in a vessel.
A form of ultrasound that can be used to hear a fetus’s heartbeat. This test can tell the amount of blood flow through blood vessels.
The output readings of an Echocardiogram; such as blood velocities in the heart chambers and vessels and heart rhythms.
Technique for calculating the relative velocity between two points by measuring the shift in frequency of a sound wave transmitted from one point to the other.
An ultrasound method of examining blood vessels.
effect = sound + movement à modified frequency (analysis of new – old indicates the velocity of a moving structure, e.g., blood flow)
Ultrasound device that a technician may use to sense the presence or absence of flow in blood vessels.
A diagnostic tool that uses low intensity ultrasound to detect blood flow velocity in arteries or veins.
A non-invasive study which uses sound waves to show the flow in a blood vessel and can be used to determine the degree of narrowing (percent stenosis) of the vessel. A wand is placed on the skin over the vessel to be imaged. This study has no risks and is not painful.
The Doppler effect, used to convert the fetal heart rate into sound.
An ultrasound study that evaluates the direction and velocity of blood flow.
A tool used to detect blood flow in an artery or vein.
(NATIONAL WEATHER SERVICE DOPPLER WEATHER RADAR) - A new Weather Surveillance Radar (WSR-88D) system developed in 1988. About 120 systems are installed at Weather Forecast Offices. An additional 24 systems are at Department of Defense (Air Force Bases) sites. This powerful and sensitive Doppler system generates many useful products for meteorologists, among them: standard reflectivity "echoes," wind "velocity" or atmospheric air motion pictures, and areal 1-hour, 3-hour, or storm-total precipitation images.
19th century physicist who discovered the variation in the wavelength of waves caused by motion of the source.
A type of ultrasound that measures blood flow.
A device which employs ultrasound to listen to the fetal heart. Sometimes referred to as a Doptone.
Named after the Austrian physicist Doppler. The Doppler effect makes use of the fact that any wave-form energy (sound, light) reflected from a moving object, will change in frequency causing higher frequency (higher tones, colour toward violet) if the object moves toward the observer and lower frequency (deeper tones, colour toward red) if the object moves away from the observer. This property can be used to calculate the speed of the moving object. In ultrasound, sound waves are reflected from thousands of blood cells moving through the blood vessels, enabling us to calculate the speed and direction of the blood in that particular vessel.
a form of ultrasound where information can be obtained on flowing blood in arteries and veins. The information can be represented as Colour Doppler (where the blood flow is shown as blue and red), or Duplex (where velocity of blood flow can be measured). See vascular ultrasound.
An instrument for detecting blood flow by ultrasonic means. An ultrasound beam is passed into the body and this is reflected from moving structures at a frequency higher than the transmitted frequency. The resultant frequency shift is amplified and presented as a sound. graphic or spectral display.
flow ultrasonography: Measures and visually record changes in the frequency of a ultrasonic wave, indicative of the change in velocity of the blood flow in underlying vessels.
Using radio waves to detect and measure blood flow.
A listening device that a doctor uses to hear a fetal heartbeat is called doppler.
A machine that uses ultrasound to detect the fetal heart.
